from django.db import models
from django.contrib.auth.models import AbstractUser
from itsdangerous import TimedJSONWebSignatureSerializer as Serializer, BadData
from django.conf import settings
from meiduo_mall.utils.BaseModel import BaseModel

# Create your models here.


# 我们重写用户模型类, 继承自 AbstractUser





class User(AbstractUser):
    """自定义用户模型类"""

    # 额外增加 mobile 字段
    mobile = models.CharField(max_length=11,
                              unique=True,
                              verbose_name='手机号')

    # 新增email_active 字段
    # 用于记录邮箱是否激活，默认为False,未激活
    email_active = models.BooleanField(default=False,
                                       verbose_name='邮箱验证状态')

    # 新增 默认地址的外键
    default_address = models.ForeignKey('address',
                                        related_name='users',
                                        null=True,
                                        blank=True,
                                        on_delete=models.SET_NULL,
                                        verbose_name='默认地址')


    # 对当前表进行相关设置:
    class Meta:
        db_table = 'tb_users'
        verbose_name = '用户'
        verbose_name_plural = verbose_name

    # 在 str 魔法方法中, 返回用户名称
    def __str__(self):
        return self.username


    # 生成邮箱验证链接
    def generate_verify_email_url(self):
        """
        生成邮箱验证链接
        :return: verify_url
        """

        # 调用itsdangerous 中的类生成对象
        # 有效期：1天
        serializer = Serializer(settings.SECRET_KEY,
                                expires_in=3600 * 24)

        # 拼接参数
        data = {'user_id': self.id, 'email': self.email}

        # 加密生成token值，这个值是bytes类型，需要解码为str
        token = serializer.dumps(data).decode()

        # 拼接url
        verify_url = settings.EMAIL_VERIFY_URL + token

        # 返回
        return verify_url


    # 定义验证函数
    @staticmethod
    def check_verify_email_token(token):
        """
        验证token并提取user
        :param token: 用户信息签名后的结果， 即加密后的data = {'user_id': self.id, 'email': self.email}
        :return: user, None
        """

        # 调用itsdangerous类，生成对象
        # 邮件验证链接有效期： 1天

        serializer = Serializer(settings.SECRET_KEY,
                                expires_in=3600 *24)

        try:
            # 加密传入的token,获取数据data
            data = serializer.loads(token)
        except BadData:
            # 如果传入的token中没有值，则报错
            return None
        else:
            # 如果有值，则获取
            user_id = data.get('user_id')
            email = data.get('email')

        # 获取到值之后，尝试从User 表中获取对应的用户
        try:
            user = User.objects.get(id=user_id, email=email)
        except User.DoesNotExist:
            # 如果用户不存在，则返回None
            return None
        else:
            # 如果user存在，则返回user
            return user




# 新增地址的模型类，放到User模型类的下方
class Address(BaseModel):
    """用户地址"""

    user = models.ForeignKey(User,
                             on_delete=models.CASCADE,
                             related_name='addresses',
                             verbose_name='用户')

    province = models.ForeignKey('areas.Area',
                                 on_delete=models.PROTECT,
                                 related_name='province_addresses',
                                 verbose_name='省')

    city = models.ForeignKey('areas.Area',
                             on_delete=models.PROTECT,
                             related_name='city_addresses',
                             verbose_name='市')

    district = models.ForeignKey('areas.Area',
                                 on_delete=models.PROTECT,
                                 related_name='district_addresses',
                                 verbose_name='区')

    title = models.CharField(max_length=20, verbose_name='地址名称')
    receiver = models.CharField(max_length=20, verbose_name='收货人')
    place = models.CharField(max_length=50, verbose_name='地址')
    mobile = models.CharField(max_length=11, verbose_name='手机号')
    tel = models.CharField(max_length=20,
                           null=True,
                           blank=True,
                           default='',
                           verbose_name='固定电话')
    email = models.CharField(max_length=30,
                             null=True,
                             blank=True,
                             default='',
                             verbose_name='电子邮箱')
    is_deleted = models.BooleanField(default=False, verbose_name='逻辑删除')


    class Meta:
        db_table = 'tb_address'
        verbose_name = '用户地址'
        verbose_name_plural = verbose_name
        ordering = ['-update_time']


